#64A1CC

CSS

:root {
  --sub-zero: #64a1cc;
  --sub-zero-rgb: 100 161 204;
  --sub-zero-oklch: oklch(0.684 0.09 240.6);
}

.element {
  color: var(--sub-zero);
  background-color: hsl(205 50% 60%);
  border-color: oklch(0.684 0.09 240.6);
}

Tailwind CSS v4

@theme {
  --color-sub-zero: #64a1cc;
  --color-sub-zero-50: #e0f9ff;
  --color-sub-zero-100: #cfecff;
  --color-sub-zero-200: #b4daf8;
  --color-sub-zero-300: #8fbee2;
  --color-sub-zero-400: #6ca6cf;
  --color-sub-zero-500: #498dbc;
  --color-sub-zero-600: #3f789f;
  --color-sub-zero-700: #32607f;
  --color-sub-zero-800: #21475e;
  --color-sub-zero-900: #163142;
  --color-sub-zero-950: #071d2a;
}

SCSS

$sub-zero: #64a1cc;
$sub-zero-rgb: 100, 161, 204;
$sub-zero-light: mix(#fff, $sub-zero, 20%);
$sub-zero-dark: mix(#000, $sub-zero, 20%);

.element {
  color: $sub-zero;
  box-shadow: 0 0 0 2px rgba($sub-zero, 0.35);
}